CheckSoureCompiles: Add a unified way to check if a source compiles

Help/manual/cmake-modules.7.rst

@@ -45,6 +45,7 @@ These modules are loaded using the :command:`include` command.
    /module/CheckOBJCXXSourceRuns
    /module/CheckPIESupported
    /module/CheckPrototypeDefinition
+   /module/CheckSourceCompiles
    /module/CheckStructHasMember
    /module/CheckSymbolExists
    /module/CheckTypeSize

Help/module/CheckSourceCompiles.rst

@@ -0,0 +1 @@
+.. cmake-module:: ../../Modules/CheckSourceCompiles.cmake

Help/release/dev/check-source-modules.rst

@@ -0,0 +1,6 @@
+check-source-modules
+^^^^^^^^^^^^^^^^^^^^
+
+* The :module:`CheckSourceCompiles` module has been added to
+  generalize :module:`CheckCSourceCompiles` and
+  :module:`CheckCXXSourceCompiles` to more languages.

Modules/CheckCSourceCompiles.cmake

@@ -66,80 +66,8 @@ Check if given C source compiles and links into an executable.
 #]=======================================================================]
 
 include_guard(GLOBAL)
+include(CheckSourceCompiles)
 
 macro(CHECK_C_SOURCE_COMPILES SOURCE VAR)
-  if(NOT DEFINED "${VAR}")
-    set(_FAIL_REGEX)
-    set(_key)
-    foreach(arg ${ARGN})
-      if("${arg}" MATCHES "^(FAIL_REGEX)$")
-        set(_key "${arg}")
-      elseif(_key)
-        list(APPEND _${_key} "${arg}")
-      else()
-        message(FATAL_ERROR "Unknown argument:\n  ${arg}\n")
-      endif()
-    endforeach()
-    set(MACRO_CHECK_FUNCTION_DEFINITIONS
-      "-D${VAR} ${CMAKE_REQUIRED_FLAGS}")
-    if(CMAKE_REQUIRED_LINK_OPTIONS)
-      set(CHECK_C_SOURCE_COMPILES_ADD_LINK_OPTIONS
-        LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS})
-    else()
-      set(CHECK_C_SOURCE_COMPILES_ADD_LINK_OPTIONS)
-    endif()
-    if(CMAKE_REQUIRED_LIBRARIES)
-      set(CHECK_C_SOURCE_COMPILES_ADD_LIBRARIES
-        LINK_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
-    else()
-      set(CHECK_C_SOURCE_COMPILES_ADD_LIBRARIES)
-    endif()
-    if(CMAKE_REQUIRED_INCLUDES)
-      set(CHECK_C_SOURCE_COMPILES_ADD_INCLUDES
-        "-DINCLUDE_DIRECTORIES:STRING=${CMAKE_REQUIRED_INCLUDES}")
-    else()
-      set(CHECK_C_SOURCE_COMPILES_ADD_INCLUDES)
-    endif()
-    file(WRITE "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.c"
-      "${SOURCE}\n")
-
-    if(NOT CMAKE_REQUIRED_QUIET)
-      message(CHECK_START "Performing Test ${VAR}")
-    endif()
-    try_compile(${VAR}
-      ${CMAKE_BINARY_DIR}
-      ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.c
-      COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS}
-      ${CHECK_C_SOURCE_COMPILES_ADD_LINK_OPTIONS}
-      ${CHECK_C_SOURCE_COMPILES_ADD_LIBRARIES}
-      CMAKE_FLAGS -DCOMPILE_DEFINITIONS:STRING=${MACRO_CHECK_FUNCTION_DEFINITIONS}
-      "${CHECK_C_SOURCE_COMPILES_ADD_INCLUDES}"
-      OUTPUT_VARIABLE OUTPUT)
-
-    foreach(_regex ${_FAIL_REGEX})
-      if("${OUTPUT}" MATCHES "${_regex}")
-        set(${VAR} 0)
-      endif()
-    endforeach()
-
-    if(${VAR})
-      set(${VAR} 1 CACHE INTERNAL "Test ${VAR}")
-      if(NOT CMAKE_REQUIRED_QUIET)
-        message(CHECK_PASS "Success")
-      endif()
-      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
-        "Performing C SOURCE FILE Test ${VAR} succeeded with the following output:\n"
-        "${OUTPUT}\n"
-        "Source file was:\n${SOURCE}\n")
-    else()
-      if(NOT CMAKE_REQUIRED_QUIET)
-        message(CHECK_FAIL "Failed")
-      endif()
-      set(${VAR} "" CACHE INTERNAL "Test ${VAR}")
-      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
-        "Performing C SOURCE FILE Test ${VAR} failed with the following output:\n"
-        "${OUTPUT}\n"
-        "Source file was:\n${SOURCE}\n")
-    endif()
-  endif()
+  check_source_compiles(C "${SOURCE}" ${VAR} ${ARGN})
 endmacro()

Modules/CheckCXXSourceCompiles.cmake

@@ -66,81 +66,8 @@ Check if given C++ source compiles and links into an executable.
 #]=======================================================================]
 
 include_guard(GLOBAL)
+include(CheckSourceCompiles)
 
 macro(CHECK_CXX_SOURCE_COMPILES SOURCE VAR)
-  if(NOT DEFINED "${VAR}")
-    set(_FAIL_REGEX)
-    set(_key)
-    foreach(arg ${ARGN})
-      if("${arg}" MATCHES "^(FAIL_REGEX)$")
-        set(_key "${arg}")
-      elseif(_key)
-        list(APPEND _${_key} "${arg}")
-      else()
-        message(FATAL_ERROR "Unknown argument:\n  ${arg}\n")
-      endif()
-    endforeach()
-
-    set(MACRO_CHECK_FUNCTION_DEFINITIONS
-      "-D${VAR} ${CMAKE_REQUIRED_FLAGS}")
-    if(CMAKE_REQUIRED_LINK_OPTIONS)
-      set(CHECK_CXX_SOURCE_COMPILES_ADD_LINK_OPTIONS
-        LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS})
-    else()
-      set(CHECK_CXX_SOURCE_COMPILES_ADD_LINK_OPTIONS)
-    endif()
-    if(CMAKE_REQUIRED_LIBRARIES)
-      set(CHECK_CXX_SOURCE_COMPILES_ADD_LIBRARIES
-        LINK_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
-    else()
-      set(CHECK_CXX_SOURCE_COMPILES_ADD_LIBRARIES)
-    endif()
-    if(CMAKE_REQUIRED_INCLUDES)
-      set(CHECK_CXX_SOURCE_COMPILES_ADD_INCLUDES
-        "-DINCLUDE_DIRECTORIES:STRING=${CMAKE_REQUIRED_INCLUDES}")
-    else()
-      set(CHECK_CXX_SOURCE_COMPILES_ADD_INCLUDES)
-    endif()
-    file(WRITE "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.cxx"
-      "${SOURCE}\n")
-
-    if(NOT CMAKE_REQUIRED_QUIET)
-      message(CHECK_START "Performing Test ${VAR}")
-    endif()
-    try_compile(${VAR}
-      ${CMAKE_BINARY_DIR}
-      ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.cxx
-      COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS}
-      ${CHECK_CXX_SOURCE_COMPILES_ADD_LINK_OPTIONS}
-      ${CHECK_CXX_SOURCE_COMPILES_ADD_LIBRARIES}
-      CMAKE_FLAGS -DCOMPILE_DEFINITIONS:STRING=${MACRO_CHECK_FUNCTION_DEFINITIONS}
-      "${CHECK_CXX_SOURCE_COMPILES_ADD_INCLUDES}"
-      OUTPUT_VARIABLE OUTPUT)
-
-    foreach(_regex ${_FAIL_REGEX})
-      if("${OUTPUT}" MATCHES "${_regex}")
-        set(${VAR} 0)
-      endif()
-    endforeach()
-
-    if(${VAR})
-      set(${VAR} 1 CACHE INTERNAL "Test ${VAR}")
-      if(NOT CMAKE_REQUIRED_QUIET)
-        message(CHECK_PASS "Success")
-      endif()
-      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
-        "Performing C++ SOURCE FILE Test ${VAR} succeeded with the following output:\n"
-        "${OUTPUT}\n"
-        "Source file was:\n${SOURCE}\n")
-    else()
-      if(NOT CMAKE_REQUIRED_QUIET)
-        message(CHECK_FAIL "Failed")
-      endif()
-      set(${VAR} "" CACHE INTERNAL "Test ${VAR}")
-      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
-        "Performing C++ SOURCE FILE Test ${VAR} failed with the following output:\n"
-        "${OUTPUT}\n"
-        "Source file was:\n${SOURCE}\n")
-    endif()
-  endif()
+  check_source_compiles(CXX "${SOURCE}" ${VAR} ${ARGN})
 endmacro()

Modules/CheckFortranSourceCompiles.cmake

@@ -87,82 +87,8 @@ Check if given Fortran source compiles and links into an executable.
 #]=======================================================================]
 
 include_guard(GLOBAL)
+include(CheckSourceCompiles)
 
 macro(CHECK_Fortran_SOURCE_COMPILES SOURCE VAR)
-  if(NOT DEFINED "${VAR}")
-    set(_FAIL_REGEX)
-    set(_SRC_EXT)
-    set(_key)
-    foreach(arg ${ARGN})
-      if("${arg}" MATCHES "^(FAIL_REGEX|SRC_EXT)$")
-        set(_key "${arg}")
-      elseif(_key)
-        list(APPEND _${_key} "${arg}")
-      else()
-        message(FATAL_ERROR "Unknown argument:\n  ${arg}\n")
-      endif()
-    endforeach()
-    if(NOT _SRC_EXT)
-      set(_SRC_EXT F)
-    endif()
-    if(CMAKE_REQUIRED_LINK_OPTIONS)
-      set(CHECK_Fortran_SOURCE_COMPILES_ADD_LINK_OPTIONS
-        LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS})
-    else()
-      set(CHECK_Fortran_SOURCE_COMPILES_ADD_LINK_OPTIONS)
-    endif()
-    if(CMAKE_REQUIRED_LIBRARIES)
-      set(CHECK_Fortran_SOURCE_COMPILES_ADD_LIBRARIES
-        LINK_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
-    else()
-      set(CHECK_Fortran_SOURCE_COMPILES_ADD_LIBRARIES)
-    endif()
-    if(CMAKE_REQUIRED_INCLUDES)
-      set(CHECK_Fortran_SOURCE_COMPILES_ADD_INCLUDES
-        "-DINCLUDE_DIRECTORIES:STRING=${CMAKE_REQUIRED_INCLUDES}")
-    else()
-      set(CHECK_Fortran_SOURCE_COMPILES_ADD_INCLUDES)
-    endif()
-    file(WRITE "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.${_SRC_EXT}"
-      "${SOURCE}\n")
-
-    if(NOT CMAKE_REQUIRED_QUIET)
-      message(CHECK_START "Performing Test ${VAR}")
-    endif()
-    try_compile(${VAR}
-      ${CMAKE_BINARY_DIR}
-      ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.${_SRC_EXT}
-      COMPILE_DEFINITIONS -D${VAR} ${CMAKE_REQUIRED_DEFINITIONS}
-      ${CHECK_Fortran_SOURCE_COMPILES_ADD_LINK_OPTIONS}
-      ${CHECK_Fortran_SOURCE_COMPILES_ADD_LIBRARIES}
-      CMAKE_FLAGS -DCOMPILE_DEFINITIONS:STRING=${CMAKE_REQUIRED_FLAGS}
-      "${CHECK_Fortran_SOURCE_COMPILES_ADD_INCLUDES}"
-      OUTPUT_VARIABLE OUTPUT)
-
-    foreach(_regex ${_FAIL_REGEX})
-      if("${OUTPUT}" MATCHES "${_regex}")
-        set(${VAR} 0)
-      endif()
-    endforeach()
-
-    if(${VAR})
-      set(${VAR} 1 CACHE INTERNAL "Test ${VAR}")
-      if(NOT CMAKE_REQUIRED_QUIET)
-        message(CHECK_PASS "Success")
-      endif()
-      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
-        "Performing Fortran SOURCE FILE Test ${VAR} succeeded with the following output:\n"
-        "${OUTPUT}\n"
-        "Source file was:\n${SOURCE}\n")
-    else()
-      if(NOT CMAKE_REQUIRED_QUIET)
-        message(CHECK_FAIL "Failed")
-      endif()
-      set(${VAR} "" CACHE INTERNAL "Test ${VAR}")
-      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
-        "Performing Fortran SOURCE FILE Test ${VAR} failed with the following output:\n"
-        "${OUTPUT}\n"
-        "Source file was:\n${SOURCE}\n")
-    endif()
-  endif()
+  check_source_compiles(Fortran "${SOURCE}" ${VAR} ${ARGN})
 endmacro()

Modules/CheckLinkerFlag.cmake

@@ -51,7 +51,7 @@ function(CHECK_LINKER_FLAG _lang _flag _var)
     return()
   endif()
 
-  include (Check${_lang}SourceCompiles)
+  include (CheckSourceCompiles)
 
   set(CMAKE_REQUIRED_LINK_OPTIONS "${_flag}")
 
@@ -74,7 +74,7 @@ function(CHECK_LINKER_FLAG _lang _flag _var)
   endif()
   check_compiler_flag_common_patterns(_common_patterns)
 
-  cmake_language (CALL check_${_lang}_source_compiles "${_source}" ${_var} ${_common_patterns})
+  check_source_compiles(${_lang} "${_source}" ${_var} ${_common_patterns})
 
   foreach(v IN LISTS _locale_vars)
     set(ENV{${v}} ${_locale_vars_saved_${v}})

Modules/CheckOBJCSourceCompiles.cmake

@@ -68,80 +68,8 @@ Check if given Objective-C source compiles and links into an executable.
 #]=======================================================================]
 
 include_guard(GLOBAL)
+include(CheckSourceCompiles)
 
 macro(CHECK_OBJC_SOURCE_COMPILES SOURCE VAR)
-  if(NOT DEFINED "${VAR}")
-    set(_FAIL_REGEX)
-    set(_key)
-    foreach(arg ${ARGN})
-      if("${arg}" MATCHES "^(FAIL_REGEX)$")
-        set(_key "${arg}")
-      elseif(_key)
-        list(APPEND _${_key} "${arg}")
-      else()
-        message(FATAL_ERROR "Unknown argument:\n  ${arg}\n")
-      endif()
-    endforeach()
-    set(MACRO_CHECK_FUNCTION_DEFINITIONS
-      "-D${VAR} ${CMAKE_REQUIRED_FLAGS}")
-    if(CMAKE_REQUIRED_LINK_OPTIONS)
-      set(CHECK_OBJC_SOURCE_COMPILES_ADD_LINK_OPTIONS
-        LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS})
-    else()
-      set(CHECK_OBJC_SOURCE_COMPILES_ADD_LINK_OPTIONS)
-    endif()
-    if(CMAKE_REQUIRED_LIBRARIES)
-      set(CHECK_OBJC_SOURCE_COMPILES_ADD_LIBRARIES
-        LINK_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
-    else()
-      set(CHECK_OBJC_SOURCE_COMPILES_ADD_LIBRARIES)
-    endif()
-    if(CMAKE_REQUIRED_INCLUDES)
-      set(CHECK_OBJC_SOURCE_COMPILES_ADD_INCLUDES
-        "-DINCLUDE_DIRECTORIES:STRING=${CMAKE_REQUIRED_INCLUDES}")
-    else()
-      set(CHECK_OBJC_SOURCE_COMPILES_ADD_INCLUDES)
-    endif()
-    file(WRITE "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.m"
-      "${SOURCE}\n")
-
-    if(NOT CMAKE_REQUIRED_QUIET)
-      message(CHECK_START "Performing Test ${VAR}")
-    endif()
-    try_compile(${VAR}
-      ${CMAKE_BINARY_DIR}
-      ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.m
-      COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS}
-      ${CHECK_OBJC_SOURCE_COMPILES_ADD_LINK_OPTIONS}
-      ${CHECK_OBJC_SOURCE_COMPILES_ADD_LIBRARIES}
-      CMAKE_FLAGS -DCOMPILE_DEFINITIONS:STRING=${MACRO_CHECK_FUNCTION_DEFINITIONS}
-      "${CHECK_OBJC_SOURCE_COMPILES_ADD_INCLUDES}"
-      OUTPUT_VARIABLE OUTPUT)
-
-    foreach(_regex ${_FAIL_REGEX})
-      if("${OUTPUT}" MATCHES "${_regex}")
-        set(${VAR} 0)
-      endif()
-    endforeach()
-
-    if(${VAR})
-      set(${VAR} 1 CACHE INTERNAL "Test ${VAR}")
-      if(NOT CMAKE_REQUIRED_QUIET)
-        message(CHECK_PASS "Success")
-      endif()
-      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
-        "Performing Objective-C SOURCE FILE Test ${VAR} succeeded with the following output:\n"
-        "${OUTPUT}\n"
-        "Source file was:\n${SOURCE}\n")
-    else()
-      if(NOT CMAKE_REQUIRED_QUIET)
-        message(CHECK_FAIL "Failed")
-      endif()
-      set(${VAR} "" CACHE INTERNAL "Test ${VAR}")
-      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
-        "Performing Objective-C SOURCE FILE Test ${VAR} failed with the following output:\n"
-        "${OUTPUT}\n"
-        "Source file was:\n${SOURCE}\n")
-    endif()
-  endif()
+  check_source_compiles(OBJC "${SOURCE}" ${VAR} ${ARGN})
 endmacro()

Modules/CheckOBJCXXSourceCompiles.cmake

@@ -68,81 +68,8 @@ Check if given Objective-C++ source compiles and links into an executable.
 #]=======================================================================]
 
 include_guard(GLOBAL)
+include(CheckSourceCompiles)
 
 macro(CHECK_OBJCXX_SOURCE_COMPILES SOURCE VAR)
-  if(NOT DEFINED "${VAR}")
-    set(_FAIL_REGEX)
-    set(_key)
-    foreach(arg ${ARGN})
-      if("${arg}" MATCHES "^(FAIL_REGEX)$")
-        set(_key "${arg}")
-      elseif(_key)
-        list(APPEND _${_key} "${arg}")
-      else()
-        message(FATAL_ERROR "Unknown argument:\n  ${arg}\n")
-      endif()
-    endforeach()
-
-    set(MACRO_CHECK_FUNCTION_DEFINITIONS
-      "-D${VAR} ${CMAKE_REQUIRED_FLAGS}")
-    if(CMAKE_REQUIRED_LINK_OPTIONS)
-      set(CHECK_OBJCXX_SOURCE_COMPILES_ADD_LINK_OPTIONS
-        LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS})
-    else()
-      set(CHECK_OBJCXX_SOURCE_COMPILES_ADD_LINK_OPTIONS)
-    endif()
-    if(CMAKE_REQUIRED_LIBRARIES)
-      set(CHECK_OBJCXX_SOURCE_COMPILES_ADD_LIBRARIES
-        LINK_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
-    else()
-      set(CHECK_OBJCXX_SOURCE_COMPILES_ADD_LIBRARIES)
-    endif()
-    if(CMAKE_REQUIRED_INCLUDES)
-      set(CHECK_OBJCXX_SOURCE_COMPILES_ADD_INCLUDES
-        "-DINCLUDE_DIRECTORIES:STRING=${CMAKE_REQUIRED_INCLUDES}")
-    else()
-      set(CHECK_OBJCXX_SOURCE_COMPILES_ADD_INCLUDES)
-    endif()
-    file(WRITE "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.mm"
-      "${SOURCE}\n")
-
-    if(NOT CMAKE_REQUIRED_QUIET)
-      message(CHECK_START "Performing Test ${VAR}")
-    endif()
-    try_compile(${VAR}
-      ${CMAKE_BINARY_DIR}
-      ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.mm
-      COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS}
-      ${CHECK_OBJCXX_SOURCE_COMPILES_ADD_LINK_OPTIONS}
-      ${CHECK_OBJCXX_SOURCE_COMPILES_ADD_LIBRARIES}
-      CMAKE_FLAGS -DCOMPILE_DEFINITIONS:STRING=${MACRO_CHECK_FUNCTION_DEFINITIONS}
-      "${CHECK_OBJCXX_SOURCE_COMPILES_ADD_INCLUDES}"
-      OUTPUT_VARIABLE OUTPUT)
-
-    foreach(_regex ${_FAIL_REGEX})
-      if("${OUTPUT}" MATCHES "${_regex}")
-        set(${VAR} 0)
-      endif()
-    endforeach()
-
-    if(${VAR})
-      set(${VAR} 1 CACHE INTERNAL "Test ${VAR}")
-      if(NOT CMAKE_REQUIRED_QUIET)
-        message(CHECK_PASS "Success")
-      endif()
-      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
-        "Performing Objective-C++ SOURCE FILE Test ${VAR} succeeded with the following output:\n"
-        "${OUTPUT}\n"
-        "Source file was:\n${SOURCE}\n")
-    else()
-      if(NOT CMAKE_REQUIRED_QUIET)
-        message(CHECK_FAIL "Failed")
-      endif()
-      set(${VAR} "" CACHE INTERNAL "Test ${VAR}")
-      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
-        "Performing Objective-C++ SOURCE FILE Test ${VAR} failed with the following output:\n"
-        "${OUTPUT}\n"
-        "Source file was:\n${SOURCE}\n")
-    endif()
-  endif()
+  check_source_compiles(OBJCXX "${SOURCE}" ${VAR} ${ARGN})
 endmacro()

Modules/CheckSourceCompiles.cmake

@@ -0,0 +1,192 @@
+# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+# file Copyright.txt or https://cmake.org/licensing for details.
+
+
+#[=======================================================================[.rst:
+CheckSourceCompiles
+----------------------
+
+.. versionadded:: 3.19
+
+Check if given source compiles and links into an executable.
+
+.. command:: check_source_compiles
+
+  .. code-block:: cmake
+
+    check_source_compiles(<lang> <code> <resultVar>
+                          [FAIL_REGEX <regex1> [<regex2>...]]
+                          [SRC_EXT <extension>])
+
+  Check that the source supplied in ``<code>`` can be compiled as a source
+  file for the requested language and linked as an executable (so it must
+  contain at least a ``main()`` function). The result will be stored in the
+  internal cache variable specified by ``<resultVar>``, with a boolean true
+  value for success and boolean false for failure. If ``FAIL_REGEX`` is
+  provided, then failure is determined by checking if anything in the output
+  matches any of the specified regular expressions.
+
+  By default, the test source file will be given a file extension that matches
+  the requested language. The ``SRC_EXT`` option can be used to override this
+  with ``.<extension>`` instead.
+
+  The underlying check is performed by the :command:`try_compile` command. The
+  compile and link commands can be influenced by setting any of the following
+  variables prior to calling ``check_source_compiles()``:
+
+  ``CMAKE_REQUIRED_FLAGS``
+    Additional flags to pass to the compiler. Note that the contents of
+    :variable:`CMAKE_<LANG>_FLAGS <CMAKE_<LANG>_FLAGS>` and its associated
+    configuration-specific variable are automatically added to the compiler
+    command before the contents of ``CMAKE_REQUIRED_FLAGS``.
+
+  ``CMAKE_REQUIRED_DEFINITIONS``
+    A :ref:`;-list <CMake Language Lists>` of compiler definitions of the form
+    ``-DFOO`` or ``-DFOO=bar``. A definition for the name specified by
+    ``<resultVar>`` will also be added automatically.
+
+  ``CMAKE_REQUIRED_INCLUDES``
+    A :ref:`;-list <CMake Language Lists>` of header search paths to pass to
+    the compiler. These will be the only header search paths used by
+    ``try_compile()``, i.e. the contents of the :prop_dir:`INCLUDE_DIRECTORIES`
+    directory property will be ignored.
+
+  ``CMAKE_REQUIRED_LINK_OPTIONS``
+    A :ref:`;-list <CMake Language Lists>` of options to add to the link
+    command (see :command:`try_compile` for further details).
+
+  ``CMAKE_REQUIRED_LIBRARIES``
+    A :ref:`;-list <CMake Language Lists>` of libraries to add to the link
+    command. These can be the name of system libraries or they can be
+    :ref:`Imported Targets <Imported Targets>` (see :command:`try_compile` for
+    further details).
+
+  ``CMAKE_REQUIRED_QUIET``
+    If this variable evaluates to a boolean true value, all status messages
+    associated with the check will be suppressed.
+
+  The check is only performed once, with the result cached in the variable
+  named by ``<resultVar>``. Every subsequent CMake run will re-use this cached
+  value rather than performing the check again, even if the ``<code>`` changes.
+  In order to force the check to be re-evaluated, the variable named by
+  ``<resultVar>`` must be manually removed from the cache.
+
+#]=======================================================================]
+
+
+include_guard(GLOBAL)
+
+cmake_policy(PUSH)
+cmake_policy(SET CMP0054 NEW) # if() quoted variables not dereferenced
+cmake_policy(SET CMP0057 NEW) # if() supports IN_LIST
+
+function(CHECK_SOURCE_COMPILES _lang _source _var)
+  if(NOT DEFINED "${_var}")
+
+    if(_lang STREQUAL C)
+      set(_lang_textual "C")
+      set(_lang_ext "c")
+    elseif(_lang STREQUAL CXX)
+      set(_lang_textual "C++")
+      set(_lang_ext "cxx")
+    elseif(_lang STREQUAL Fortran)
+      set(_lang_textual "Fortran")
+      set(_lang_ext "F")
+    elseif(_lang STREQUAL OBJC)
+      set(_lang_textual "Objective-C")
+      set(_lang_ext "m")
+    elseif(_lang STREQUAL OBJCXX)
+      set(_lang_textual "Objective-C++")
+      set(_lang_ext "mm")
+    else()
+      message (SEND_ERROR "check_source_compiles: ${_lang}: unknown language.")
+      return()
+    endif()
+
+    get_property (_supported_languages GLOBAL PROPERTY ENABLED_LANGUAGES)
+    if (NOT _lang IN_LIST _supported_languages)
+      message (SEND_ERROR "check_source_compiles: ${_lang}: needs to be enabled before use.")
+      return()
+    endif()
+
+    set(_FAIL_REGEX)
+    set(_SRC_EXT)
+    set(_key)
+    foreach(arg ${ARGN})
+      if("${arg}" MATCHES "^(FAIL_REGEX|SRC_EXT)$")
+        set(_key "${arg}")
+      elseif(_key)
+        list(APPEND _${_key} "${arg}")
+      else()
+        message(FATAL_ERROR "Unknown argument:\n  ${arg}\n")
+      endif()
+    endforeach()
+
+    if(NOT _SRC_EXT)
+      set(_SRC_EXT ${_lang_ext})
+    endif()
+
+    if(CMAKE_REQUIRED_LINK_OPTIONS)
+      set(CHECK_${LANG}_SOURCE_COMPILES_ADD_LINK_OPTIONS
+        LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS})
+    else()
+      set(CHECK_${LANG}_SOURCE_COMPILES_ADD_LINK_OPTIONS)
+    endif()
+    if(CMAKE_REQUIRED_LIBRARIES)
+      set(CHECK_${LANG}_SOURCE_COMPILES_ADD_LIBRARIES
+        LINK_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
+    else()
+      set(CHECK_${LANG}_SOURCE_COMPILES_ADD_LIBRARIES)
+    endif()
+    if(CMAKE_REQUIRED_INCLUDES)
+      set(CHECK_${LANG}_SOURCE_COMPILES_ADD_INCLUDES
+        "-DINCLUDE_DIRECTORIES:STRING=${CMAKE_REQUIRED_INCLUDES}")
+    else()
+      set(CHECK_${LANG}_SOURCE_COMPILES_ADD_INCLUDES)
+    endif()
+    file(WRITE "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.${_SRC_EXT}"
+      "${_source}\n")
+
+    if(NOT CMAKE_REQUIRED_QUIET)
+      message(CHECK_START "Performing Test ${_var}")
+    endif()
+    try_compile(${_var}
+      ${CMAKE_BINARY_DIR}
+      ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.${_SRC_EXT}
+      COMPILE_DEFINITIONS -D${_var} ${CMAKE_REQUIRED_DEFINITIONS}
+      ${CHECK_${LANG}_SOURCE_COMPILES_ADD_LINK_OPTIONS}
+      ${CHECK_${LANG}_SOURCE_COMPILES_ADD_LIBRARIES}
+      CMAKE_FLAGS -DCOMPILE_DEFINITIONS:STRING=${CMAKE_REQUIRED_FLAGS}
+      "${CHECK_${LANG}_SOURCE_COMPILES_ADD_INCLUDES}"
+      OUTPUT_VARIABLE OUTPUT)
+
+    foreach(_regex ${_FAIL_REGEX})
+      if("${OUTPUT}" MATCHES "${_regex}")
+        set(${_var} 0)
+      endif()
+    endforeach()
+
+    if(${_var})
+      set(${_var} 1 CACHE INTERNAL "Test ${_var}")
+      if(NOT CMAKE_REQUIRED_QUIET)
+        message(CHECK_PASS "Success")
+      endif()
+      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
+        "Performing ${_lang_textual} SOURCE FILE Test ${_var} succeeded with the following output:\n"
+        "${OUTPUT}\n"
+        "Source file was:\n${_source}\n")
+    else()
+      if(NOT CMAKE_REQUIRED_QUIET)
+        message(CHECK_FAIL "Failed")
+      endif()
+      set(${_var} "" CACHE INTERNAL "Test ${_var}")
+      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
+        "Performing ${_lang_textual} SOURCE FILE Test ${_var} failed with the following output:\n"
+        "${OUTPUT}\n"
+        "Source file was:\n${_source}\n")
+    endif()
+  endif()
+
+endfunction()
+
+cmake_policy(POP)

Tests/RunCMake/CMakeLists.txt

@@ -534,6 +534,7 @@ add_RunCMake_test(target_compile_features)
 add_RunCMake_test(target_compile_options -DCMAKE_C_COMPILER_ID=${CMAKE_C_COMPILER_ID})
 add_RunCMake_test(target_include_directories)
 add_RunCMake_test(target_sources)
+add_RunCMake_test(CheckSourceCompiles)
 add_RunCMake_test(CheckModules)
 add_RunCMake_test(CheckIPOSupported)
 if (CMAKE_SYSTEM_NAME MATCHES "(Linux|Darwin)"
@@ -542,6 +543,7 @@ if (CMAKE_SYSTEM_NAME MATCHES "(Linux|Darwin)"
                                     -DCMAKE_Fortran_COMPILER_ID=${CMAKE_Fortran_COMPILER_ID})
 endif()
 
+
 add_RunCMake_test(CommandLine -DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME} -DCYGWIN=${CYGWIN} -DPYTHON_EXECUTABLE=${PYTHON_EXECUTABLE})
 add_RunCMake_test(CommandLineTar)
 

Tests/RunCMake/CheckSourceCompiles/CMakeLists.txt

@@ -0,0 +1,5 @@
+cmake_minimum_required(VERSION 3.13)
+
+project(${RunCMake_TEST} LANGUAGES NONE)
+
+include(${RunCMake_TEST}.cmake)

Tests/RunCMake/CheckSourceCompiles/CheckCSourceCompiles.cmake

@@ -0,0 +1,13 @@
+
+enable_language (C)
+include(CheckSourceCompiles)
+
+check_source_compiles(C "I don't build" SHOULD_FAIL)
+if(SHOULD_FAIL)
+  message(SEND_ERROR "invalid C source didn't fail.")
+endif()
+
+check_source_compiles(C "int main() {return 0;}" SHOULD_BUILD)
+if(NOT SHOULD_BUILD)
+  message(SEND_ERROR "Test fail for valid C source.")
+endif()

Tests/RunCMake/CheckSourceCompiles/CheckCXXSourceCompiles.cmake

@@ -0,0 +1,26 @@
+
+enable_language (CXX)
+include(CheckSourceCompiles)
+
+check_source_compiles(CXX "I don't build" SHOULD_FAIL)
+if(SHOULD_FAIL)
+  message(SEND_ERROR "invalid CXX source didn't fail.")
+endif()
+
+check_source_compiles(CXX [=[
+  #include <vector>
+  int main() {
+    return 0;
+  }
+]=]
+ SHOULD_BUILD)
+if(NOT SHOULD_BUILD)
+  message(SEND_ERROR "Test fail for valid CXX source.")
+endif()
+
+check_source_compiles(CXX "void l(char const (&x)[2]){}; int main() { l(\"\\n\"); return 0;}"
+ SHOULD_BUILD_COMPLEX)
+
+if(NOT SHOULD_BUILD_COMPLEX)
+  message(SEND_ERROR "Test fail for valid CXX complex source.")
+endif()

Tests/RunCMake/CheckSourceCompiles/CheckFortranSourceCompiles.cmake

@@ -0,0 +1,14 @@
+
+
+enable_language (Fortran)
+include(CheckSourceCompiles)
+
+check_source_compiles(Fortran [=[
+      PROGRAM TEST_HAVE_PRINT
+        PRINT *, 'Hello'
+      END
+]=] SHOULD_BUILD)
+
+if(NOT SHOULD_BUILD)
+  message(SEND_ERROR "Test fail for valid Fortran source.")
+endif()

Tests/RunCMake/CheckSourceCompiles/CheckOBJCSourceCompiles.cmake

@@ -0,0 +1,14 @@
+enable_language (OBJC)
+include(CheckSourceCompiles)
+
+check_source_compiles(OBJC [[
+  #import <Foundation/Foundation.h>
+  int main() {
+    NSObject *foo;
+    return 0;
+  }
+]] SHOULD_BUILD)
+
+if(NOT SHOULD_BUILD)
+  message(SEND_ERROR "Test fail for valid OBJC source.")
+endif()

Tests/RunCMake/CheckSourceCompiles/CheckOBJCXXSourceCompiles.cmake

@@ -0,0 +1,17 @@
+enable_language (OBJCXX)
+include(CheckSourceCompiles)
+
+check_source_compiles(OBJCXX [[
+  #include <vector>
+  #import <Foundation/Foundation.h>
+  int main() {
+    std::vector<int> v;
+    NSObject *foo;
+    return 0;
+  }
+]] SHOULD_BUILD)
+
+
+if(NOT SHOULD_BUILD)
+  message(SEND_ERROR "Test fail for OBJCXX source.")
+endif()

Tests/RunCMake/CheckSourceCompiles/NonExistentLanguage-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/CheckSourceCompiles/NonExistentLanguage-stderr.txt

@@ -0,0 +1,2 @@
+CMake Error at .*CheckSourceCompiles\.cmake:[0-9]+ \(message\):
+  check_source_compiles: FAKE_LANG: unknown language.

Tests/RunCMake/CheckSourceCompiles/NonExistentLanguage.cmake

@@ -0,0 +1,3 @@
+
+include(CheckSourceCompiles)
+check_source_compiles(FAKE_LANG "int main() {return 0;}" SHOULD_BUILD)

Tests/RunCMake/CheckSourceCompiles/NotEnabledLanguage-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/CheckSourceCompiles/NotEnabledLanguage-stderr.txt

@@ -0,0 +1,2 @@
+CMake Error at .*CheckSourceCompiles\.cmake:[0-9]+ \(message\):
+  check_source_compiles: C: needs to be enabled before use.

Tests/RunCMake/CheckSourceCompiles/NotEnabledLanguage.cmake

@@ -0,0 +1,3 @@
+
+include(CheckSourceCompiles)
+check_source_compiles(C "int main() {return 0;}" SHOULD_BUILD)

Tests/RunCMake/CheckSourceCompiles/RunCMakeTest.cmake

@@ -0,0 +1,16 @@
+include(RunCMake)
+
+run_cmake(NotEnabledLanguage)
+run_cmake(NonExistentLanguage)
+
+run_cmake(CheckCSourceCompiles)
+run_cmake(CheckCXXSourceCompiles)
+
+if (APPLE)
+  run_cmake(CheckOBJCSourceCompiles)
+  run_cmake(CheckOBJCXXSourceCompiles)
+endif()
+
+if (CMAKE_Fortran_COMPILER_ID)
+  run_cmake(CheckFortranSourceCompiles)
+endif()